Sheet separator

ABSTRACT

A sheet separator. The sheet separator includes a main body, a frictional member, and an elastic member. The main body is rotatable with a slot being longitudinally parallel to the moving direction of the medium. The frictional member is disposed in the slot and contacts the medium. When feeding, the medium exerts a first force on the main body through the frictional member. Moreover, the elastic member connects to the main body and exerts a second force thereon. According to the first force and the second force, the angle between the main body and the medium is adjusted.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a sheet separator, andparticularly to a sheet separator with adjustable feed angle.Description of the Related Art The application of business machines inoffices like printers, fax and copy machines have become more and morepopular. Regarding business machines processing paper, media-feedmechanism has a great influence on efficiency. Therefore, it has becomea new challenge to design a highly efficient media-feed mechanism tofeed and separate media readily.

[0003] In general, with printers as an example, an automatic media-feedmechanism is utilized to feed the media. Before printing, users normallyput the media in the media-feed mechanism. To print, media are moved outone by one through the media-feed mechanism.

[0004] Referring to FIG., 1A, an automatic media-feed mechanism has abottom surface 101 to carry the media. The roller 150 is above thebottom surface 101 to drive the media. In particular, a sheet separator103 and several smooth ribs 102 are disposed on the bottom surface 101.When the media are driven by the roller 105, the sheet separator 103separates the media one by one and the ribs 102 keep the individualmedia moving out smoothly.

[0005] In FIG. 1B, a sheet separator 103 and several ribs 102 disposedon the bottom surface 101 of the automatic media-feed mechanism areparallel to the moving direction of the media. The ribs 102 sustain andkeep the individual media sliding smoothly. In practice, the ribs 102are plastic or metal with a smooth surface and have a low frictioncoefficient. Referring to FIG. 1C, the medium is driven by the roller150 (not shown) in the direction A. The leading edge 107 of the medium105 contacts the ribs 102 when moving.

[0006] As shown in FIG. 1D, when the medium 105 moved in direction A,the leading edge 107 of the medium 105 contacts the ribs 102 and thesheet separator 103. At the same time, the ribs 102 and the sheetseparator 103 exert a frictional force on the medium 105 in direction Bopposite to the direction A. In particular, the frictional forceincreases with the stiffness of the medium 105. Thus, the driving motormay be overloaded, missing steps, and the leading edge 107 of the medium105 may be damaged by using excessively stiff media.

[0007] It is known that there are many categories of media made ofdifferent material of varying thickness (g/m2). Therefore, as shown inFIG. 1E, the sheet separating angle α is determined according to thecorresponding available medium thickness. Only the media within aparticular range of thickness are available when the sheet separatingangle a is determined. For example, the sheet separator 103 may allowonly media within stiffness of 70 g/m2 to 80 g/m2, but not for mediawith stiffness out of this range.

[0008] For this reason, the conventional sheet separator may causemultiple media feed at the same time and make the driving motor losestep by using excessively stiff media. Thus, the conventional sheetseparator is only suitable for media in a particular range of thicknessbut cannot be widely used.

SUMMARY OF THE INVENTION

[0009] It is therefore an object of the present invention to provide asheet separator with adjustable feed angle that can be widely used formedia of varying thickness.

[0010] To achieve the above object, the present invention provides asheet separator comprising a main body, a frictional member, and anelastic member. The main body is rotatable with a slot beinglongitudinally parallel to the moving direction of the medium. Thefrictional member is disposed in the slot and contacts the medium. Whenfeeding, the medium exerts a first force on the main body through thefrictional member. Moreover, the elastic member connects to the mainbody and exerts a second force thereon. According to the first force andthe second force, the angle between the main body and the medium isadjusted.

[0011] A detailed description is given in the following embodiments withreference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The aforementioned objects, features and advantages of theinvention will become apparent by referring to the following detaileddescription of the preferred embodiment with reference to theaccompanying drawings, wherein:

[0013]FIG. 1A (Prior Art) is a perspective diagram of a media-feedmechanism in a conventional business machine.

[0014]FIG. 1B (Prior Art) is a perspective diagram illustrating themedium moving along the ribs.

[0015]FIG. 1C (Prior Art) is a lateral view of FIG. 1B illustrating themedium moving along the ribs.

[0016]FIG. 1D (Prior Art) is a perspective diagram illustrating themedium moving along the ribs.

[0017]FIG. 1E (Prior Art) is a lateral view of FIG. 1D illustrating themedium moving along the ribs.

[0018]FIG. 2A is a perspective diagram of the medium separator inaccordance with the first embodiment of the present invention;

[0019]FIG. 2B is a exploded perspective diagram of FIG. 2A illustratingthe sheet separator in accordance with the first embodiment of thepresent invention;

[0020]FIG. 2C is a lateral view of FIG. 2A illustrating the sheetseparator in accordance with the first embodiment of the presentinvention;

[0021]FIG. 3A is a lateral view of the sheet separator used with thinnermedia in accordance with the first embodiment of the present invention;

[0022]FIG. 3B is a lateral view of the sheet separator used with thickermedia in accordance with the first embodiment of the present invention;

[0023]FIG. 4 is a perspective diagram of the sheet separator inaccordance with the second embodiment of the present invention;

DETAILED DESCRIPTION OF THE INVENTION

[0024] As shown in FIG. 2A, 2B and 2C, a frictional member 311 isdisposed in the slot 310 of the sheet separator 300. Additionally, thefrictional member 311 has a friction coefficient greater than the ribs102 to generate a frictional damping force on the medium 105. Inpractice, the frictional member 311 can also be substituted by otherwear-resistant material. Referring to FIG. 2A, an arm 301 is connectedto a fixed axis 312 of the business machine in a rotatable manner.Moreover, one end of a spring 317 connects to the business machine, andthe other end connects to the arm 301 to adjust the rotating angle ofthe arm 301. The arm 301 constitutes the main body of the sheetseparator 300, and the frictional member 311 is disposed in the slot 310with its top surface higher than the arm 311.

[0025] In FIG. 3A, media are placed on the top surface of the sheetseparator 300 and the leading edge 107 of the top medium 105 a contactsthe frictional member 311. AT the same time, the medium 105 a is drivenby the roller 150 and the frictional member 311 generates a frictionaldamping force to keep all the other media in the cartridge to avoidmultiple media feed.

[0026] When the thinner medium 105 a is driven by the force P from theroller 150, the top medium 105 a buckles to absorb the opposingfrictional damping force of the frictional member 311 so that the medium105 a can slide through the frictional member 311. As shown in FIG. 3B,however, when thicker media are applied, the sheet separating angle oabetween the medium 105 b and the arm 301 becomes larger by the force Pfrom roller 150 so that the frictional force generated by the frictionalmember 311 decreases and the thicker medium 105 b can slide out easily.

[0027]FIG. 4 is a perspective diagram of the sheet separator inaccordance with the second embodiment of the present invention. As shownin FIG. 4, an arm 301′ extends with a flexible sheet 317′ substitutedfor the spring 317 in the first embodiment, and a frictional member 311is disposed in the slot 310′ of the arm 301′. Moreover, the flexiblesheet 317′ contacts the base of the business machine so that the sheetseparating angle α is adjustable. Thus, the sheet separator in thesecond embodiment has the same functionality as the first embodiment.

[0028] The present invention provides a sheet separator widely suitablefor different media of varying thickness. Moreover, the sheet separatorin the present invention can reduce the incidence of paper jam ormultiple media feed with better performance and stability than before.

[0029] When the invention has been described by way of example and interms of the preferred embodiments, it is to be understood that theinvention is not limited to the disclosed embodiments. To the contrary,it is intended to cover various modifications and similar arrangements(as would be apparent to those skilled in the art). Therefore, the scopeof the appended claims should be accorded the broadest interpretation soas to encompass all such modifications and similar arrangements.

What is claimed Is:
 1. A sheet separator for a media-feed mechanism ofan apparatus feeding at least one medium, comprising: a main body,having a frictional surface contacting the medium, wherein the mediumexerts a first force on the main body when feeding; and an elasticmember connected to the main body, exerting a second force on the mainbody, wherein the angle between the main body and the medium is adjustedaccording to the first force and the second force.
 2. The sheetseparator as claimed in claim 1, wherein the main body further has anarm rotatably connected to the apparatus and the elastic member alsoconnects to the apparatus.
 3. The sheet separator as claimed in claim 1,wherein the elastic member is a spring.
 4. The sheet separator asclaimed in claim 1, wherein the elastic member is a flexible sheet. 5.The sheet separator as claimed in claim 1, wherein the frictionalsurface is made of rubber.
 6. A sheet separator for a media-feedmechanism feeding at least one medium of an apparatus, comprising; amain body, having a slot being longitudinally parallel to the movingdirection of the medium; a frictional member disposed in the slot andcontacting the medium, exerting a first force on the main body whenfeeding the medium; and an elastic member connected to the main body,exerting a second force on the main body, wherein the angle between themain body and the medium is adjusted according to the first force andthe second force.
 7. The sheet separator as claimed in claim 6, whereinthe main body further has an arm rotatably connected to the apparatusand the elastic member also connects to the apparatus.
 8. The sheetseparator as claimed in claim 6, wherein the frictional member protrudesfrom the slot.
 9. The sheet separator as claimed in claim 6, wherein theelastic member is a spring.
 10. The sheet separator as claimed in claim6, wherein the elastic member is a flexible sheet.
 11. The sheetseparator as claimed in claim 6, wherein the frictional member is madeof rubber.
 12. A media-feed mechanism of an apparatus feeding at leastone medium, comprising: a bottom surface; a sheet separator disposed onthe bottom surface having a main body, an elastic member and at leastone rib, wherein the main body has a frictional surface contacts themedium exerting a first force on the main body when feeding the medium,wherein the elastic member connected to the main body exerts a secondforce on the main body wherein the angle between the main body and themedium is adjusted according to the first force and the second force,wherein the rib is disposed on the bottom surface to sustain the leadingedge of the medium.
 13. The media-feed mechanism as claimed in claim 12,wherein the main body further has an arm rotatably connected to theapparatus and the elastic member also connects to the apparatus.
 14. Themedia-feed mechanism as claimed in claim 12, wherein the elastic memberis a spring.
 15. The media-feed mechanism as claimed in claim 12,wherein the elastic member is a flexible sheet.
 16. The media-feedmechanism as claimed in claim 12, further comprising a frictional memberserves as the frictional surface, and the rotatable main body furtherhaving a slot, wherein the frictional member is disposed in the slot andthe slot is longitudinally parallel to the moving direction of themedium.
 17. The media-feed mechanism as claimed in claim 16, wherein thefrictional member protrudes from the slot.
 18. The media-feed mechanismas claimed in claim 12, wherein the frictional surface is made ofrubber.
 19. The media-feed mechanism as claimed in claim 12, wherein afriction coefficient of the frictional surface is greater than afriction coefficient of the ribs.